No abstract available.
Postural Orthostatic Tachycardia Syndrome* ; Syncope

Humans ; Postural Orthostatic Tachycardia Syndrome

Orthostatic intolerance is the inability to tolerate an upright posture as a consequence of varying degrees of autonomic nervous system dysfunction. Orthostatic intolerance syndromes can be classified into at least 3 categories: 1) orthostatic hypotension, 2) neurally mediated (reflex) syncope, and 3) postural orthostatic tachycardia syndrome. In this review, we discuss the pathophysiology and etiologies of orthostatic hypotension and postural orthostatic tachycardia syndrome, and propose their diagnostic and therapeutic alternatives.
Autonomic Nervous System ; Hypotension, Orthostatic ; Orthostatic Intolerance* ; Postural Orthostatic Tachycardia Syndrome ; Posture ; Syncope

Orthostatic dizziness is a common type of dizziness. In general, orthostatic dizziness is provoked by standing or tilting, and subsided by supine position. The patient with orthostatic intolerance complains multiple symptoms such as dizziness, palpitation, lightheadness, fatigue and rarely syncope. Common orthostatic intolerance is orthostatic hypotension (classic, initial, transient, and delayed orthostatic hypotension) and postural orthostatic tachycardia syndrome. Transcranial Doppler is a noninvasive technique that provides real-time measurement of cerebral blood flow velocity. It can be useful for understanding the relationship between orthostatic symptoms and cerebral autoregulatory function. The reciprocal causal relationship between vestibular and autonomic dysfunction should always be kept in mind.
Cerebrovascular Circulation ; Dizziness ; Fatigue ; Humans ; Hypotension, Orthostatic ; Orthostatic Intolerance ; Postural Orthostatic Tachycardia Syndrome ; Supine Position ; Syncope

No abstract available.
Frontotemporal Dementia ; Postural Orthostatic Tachycardia Syndrome* ; Supranuclear Palsy, Progressive

Biomarkers ; Child ; Humans ; Postural Orthostatic Tachycardia Syndrome ; diagnosis

Child ; Humans ; Postural Orthostatic Tachycardia Syndrome ; diagnosis ; Tilt-Table Test

PURPOSE: Chronic day-to-day symptoms of orthostatic intolerance are the most notable features of postural orthostatic tachycardia syndrome (POTS). However, we have encountered patients with such symptoms and excessive tachycardia but with no symptoms during the tilt-table test (TTT). We aimed to investigate whether POTS patients with chronic orthostatic intolerance always present orthostatic symptoms during the TTT and analyze the factors underlying symptom manifestation during this test. METHODS: We retrospectively examined patients who presented with POTS at the Gyeongsang National University Hospital between 2008 and 2011. Diagnosis of POTS was based on chronic day-to-day orthostatic intolerance symptoms as well as excessive tachycardia during the TTT. The patients were divided two groups depending on the presentation of orthostatic symptoms during the TTT. Clinical data and the results of the TTT were compared between these groups. RESULTS: In 22 patients, 7 patients (31.8%) did not present orthostatic symptoms during the test. Diastolic blood pressure (BP) was significantly lower in the symptom-positive group. The head-up tilt resulted in a significant increase in diastolic BP in the symptom-negative group (P=0.04), while systolic BP had a tendency to decrease in the symptom-positive group (P=0.06). CONCLUSION: Significant patients with POTS did not present orthostatic symptoms during the TTT despite having chronic daily symptoms. This finding may be important for establishing definitive diagnostic criteria for pediatric POTS. Development of symptoms during TTT might be related to low diastolic BP and abnormal compensatory responses to orthostasis.
Blood Pressure ; Dizziness ; Humans ; Orthostatic Intolerance ; Postural Orthostatic Tachycardia Syndrome ; Retrospective Studies ; Tachycardia ; Tilt-Table Test

Since inappropriate sinus tachycardia (IST) occurs due to various reasons, it can be diagnosed after exclusion of all causes and diseases that may result in sinus tachycardia. In particular, it is important to differentiate postural orthostatic tachycardia syndrome (POTS), and a multidisciplinary approach is necessary for differentiating psychiatric events. In addition, whether the clinical symptoms coincide with tachycardia events should be checked before treatment. β-adrenergic blocker is the most effective drug, and exercise training is recommended for controlling clinical symptoms. Furthermore, discontinuation of smoking and alcohol consumption, and decrease in caffeine intake may be useful. Recently, ivabradine has been found effective, and catheter ablation can be considered in cases of drug refractory IST presenting with clinical symptoms.
Alcohol Drinking ; Arrhythmias, Cardiac ; Caffeine ; Catheter Ablation ; Postural Orthostatic Tachycardia Syndrome ; Smoke ; Smoking ; Tachycardia ; Tachycardia, Sinus*

Orthostatic dizziness is a common dizziness syndrome characterized by nonvertiginous lightheadedness when patients rise to stand from a sitting or supine position. Orthostatic dizziness is commonly believed to derive from orthostatic hypotension (OH) or postural tachycardia syndrome (POTS). Tilt-table test and Valsalva maneuver are standardized methods for evaluating of adrenergic autonomic function and essential for diagnosis of OH and POTS. We described the guidelines and interpretations of the tilt-table test and Valsalva maneuver.
Diagnosis ; Dizziness ; Humans ; Hypotension, Orthostatic ; Postural Orthostatic Tachycardia Syndrome ; Supine Position ; Tilt-Table Test ; Valsalva Maneuver